Atmosphere: Climate Change

Why is CO2 increasing in the atmosphere? Who is doing it? Many people think that CO2 is “pollution,” so that clean burning should be a way to eliminate greenhouse gas emissions. In this demonstration, we review basic chemistry (see illustration) to realize that producing CO2 is an inevitable product of burning any fossil fuel.

The factors at play in shaping our climate as well as the manifestation of its effects are geographic in nature. Geographic Information System (GIS) technology and methods are vital in documenting, monitoring, analyzing, and predicting these dynamic activities and interdependencies. Climate scientists and others in numerous careers and disciplines use GIS and its integrative nature to tackle these issues. You can, too.

Carbon is naturally found in the atmosphere. Carbon dioxide, or CO2, itself is not considered a pollutant. The CO2 being released from burning fossil fuels was part of the atmosphere hundreds of millions of years ago before being captured by plants and sea organisms.

The USGS has been studying glaciers in Glacier National Park since 1850. It is estimated that there were 150 glaciers in the park back then, and when the national park was established in 1910. Today only 25 glaciers remain.

Scientists go back every year to repeat photographs, as well as to examine the ice and the ecology of the landscape to see how glacial retreat is affecting plant and animal species that live there.

What is sea ice? It is simply frozen ocean water.
Why is sea ice important? While it occurs mainly in polar regions, sea ice influences our global climate. Changing amounts of sea ice can affect ocean circulations, weather patterns, and temperatures around the world. Sea ice insulates the relatively warm ocean water from the cold polar atmosphere, except where cracks in the ice allow for the exchange of heat and moisture. The exchange of salt between sea ice and the ocean alters the density of ocean waters, thus influencing ocean circulation. Many animals, such as polar bears, seals, and walruses, depend on sea ice for their habitat. These species hunt, feed, and breed on the ice.
Satellites provide the best way to observe sea ice, the factors that affect sea ice, and the ways sea ice affects global climate. Scheduled to launch in 2010, NASA’s Aquarius mission will measure global sea surface salinity with unprecedented resolution. Even small variations in sea surface salinity — the amount of salt present near the ocean’s surface — can have dramatic effects on sea ice, the water cycle, and ocean circulation.

Climate scientists around the world study greenhouse gases and the ways they affect global climate. By making your own small greenhouse in this activity, you can recreate the greenhouse effect and measure its effect on temperature.